Abstract
According to the Matthew effect, scientists who have previously been rewarded are more likely to be rewarded again. Although widely discussed, it remains contentious what explains this effect and whether it's unfair. Using data about neuroscientists, we examine three factors relevant to clarifying these issues: scientists’ fecundity in supervision, H-index and the location where they obtained a PhD. We find a correlation between location and H-index, but no association between fecundity and H-index. This suggests the Matthew effect entrenches status hierarchies in the scientific credit system not because of exploitative supervisors but because of lucky geographical factors.